Ranon Canyon is an excellent trip, as it shares some of the best parts of Claustral Canyon and also of Thunder Gorge. With the new entry, it is only a slightly longer day than Claustral.
It was first descended by a Kameruka Bushwalking Club party consisting of Barry Dunnett and Dave Lambert in 1962.
The NPWS requests that canyoners use the exit route as described for Claustral Canyon, and not to form new tracks. When returning from the Camels Hump use the old track across the Camels Saddle to the minor saddle, and down into Claustral Brook. The notes below describe this route. The exit is also shown roughly on a map. It is recommended that canyoners have previously entered Claustral via the new route before attempting to use it as an exit for Ranon.
The shorter way is via Mistake Ravine (this is "Ranon Canyon" in the Jamieson guide). Walk 600m west from the car along Bells Line of Rd to MGA578850 to a grassy open area just past the top of the hill. Walk down the scrubby ridge to the SW, then S. Scramble into the creek at MGA577847. A short way down the creek there are three short drops. These can be abseiled, handlined or climbed. Then there is a reasonable section of canyon to the junction with Ranon Brook. The creek walk is nice and flat, with very green ferns lining the walls, but the canyon is fairly open.
The longer way is to enter Ranon Brook higher up (this is "Ranon Brook Canyon" in the Jamieson guide). It is quite nice, but rather than a separate canyon, I would view it simply as a different way into the system. I wouldn't bother doing it as a canyon in its own right. Walk or drive west for 2km along Bells Line of Rd to just N of the 888 point, and head down the ridge to the ESE aiming to drop into the creek near the junction at MGA579841. There is a short canyon section just before the junction with Mistake Ravine. It starts with a 9m abseil, then a 5m abseil or hand line, a 15m drop in a couple of stages, and a 4m jump, climb down or abseil. There are a couple of other tricky climb downs. There are pools after most of the abseils, but they can be avoided with some difficulty if you want to keep your top half dry.
From the junction of Mistake Ravine and Ranon Brook, there is a bit of walking to a short drop that can be downclimbed or handlined. Immediately after this is the first abseil, from 5m to 9m into a waist deep pool, depending on anchor choice. Then follows a short section of canyon, and then another abseil of 6m. The abseils are both a bit awkward - overhung with chockstones. It is a bit further to the main drop. There are two primary ways to get down.
The first is to traverse along ledges to the right to some slings from a tree. This is quite a long direct drop - about 30m. A full 60m rope should reach but I wouldn't advise shorter.
More exciting is to scramble or handline down logs into a cavern to the left. From there are two two-stage abseils, going down four waterfalls, with pools after the first and third. The first is a 15m abseil from a large chockstone, down the first two sections of the falls to another chamber. Finally a 20m abseil down another two sections, also from a large chockstone. Both of these abseils involve a short swim across the pool between the falls.
Either way brings you out into Claustral Brook, about 100m downstream from the Black Hole of Calcutta.
700m of high quality canyon brings you to the Thunder Gorge junction. If you have time it is worth visiting Thunder Canyon from the bottom.
The creek opens out for about 500m before narrowing again. There are some tricky climb downs in the next section. There are also two longer drops of about 5m each, which often have fixed ropes in place. It is advisable to abseil the first of these drops on the right side. The second is easier, but is dangerous in high water, and should be abseiled on the right hand side in those conditions. In between these two drops is the Tunnel Swim, which can sometimes be a wade, but is usually a long cold swim up to 50m through a dark tunnel.
About 50m past the second climb down, Rainbow Ravine is a reasonably obvious sloping waterfall that comes in on your left, as the creek bends right. A further 50m past this there is a final 20m swim to the exit gully. Many parties miss this exit and end up being benighted in the canyon, so be careful.
Scramble up the exit gully for about 20m and then traverse left under the cliff to Rainbow Ravine. Head up Rainbow Ravine. There are a few tricky scrambles, and some wades (for those who carry dry socks or shoes).
Where the gully splits higher up, head up the left branch. At the top there is a small waterfall, involving two tricky scrambles. It is easier (and quicker for most parties) to avoid these scrambles by walking to the right along the ledge to the other gully, and then up a ramp and back over the top. This avoids further erosion in the already eroded gully above the waterfall. Otherwise, scramble up the waterfall. The first scramble is up a log braced with rope. The second can be made easier by stepping to the right and using the side of a good handhold for the left hand.
From there follow the obvious track up to the Camels Hump. Head down and right to the Camels Saddle, ignoring tracks off to the left, and then up a short way to the next minor saddle at MGA597834. Turn left here, and follow the track steeply downhill until you reach Claustral Brook.
A track can be followed alongside the creek for some way. Continue downstream past the junction with Dismal Dingle. There are a couple of canyon sections in here. There are two deep wades or short swims shortly before you reach the exit gully on the right at MGA589837.
Scramble up this gully and try and pick up a track that leads NNW back to the road at the sharp corner at MGA585846. Walk back along the road to your car.